Answer:
2000 years
Explanation:
A radioactive molecule will continuously decay and turn into another molecule. This nature of the radioactive molecule makes them can be used to estimate the age of an object. Half-life is the unit of time needed for radioactive molecules to decay to half of its mass. The formula for the mass remaining will be:

Where
N(t)= number of the molecule remains
N0= number of molecule initially
t= time elapsed
t1/2= half time
We have all variable besides the half time, the calculation will be:




3= 6000/ (t1/2)
t1/2= 6000/3= 2000
The half-life is 2000 years
Isotopes of the same element always have the same atomic number because the atomic number is like the identity of each element and if it is changed the element is changed for example isotopes of Carbon are: ₆C¹² , ₆C¹³ and ₆C¹⁴ and if we change the atomic number form 6 to 7 we will have Nitrogen element ₇N¹⁴
So the correct answer is Z- number (atomic number)
Answer:
Helps eliminate waste products such as urea, uric acid ammonia, and other products via urine.
It helps maintain the osmotic level of blood and plasma.
It helps maintain the electrolyte balance in the body.
And it also helps in the metabolism of those drugs that do not get metabolized in the liver.
Explanation:
<em>"The excretory system is a passive biological system that removes excess, unnecessary materials from the body fluids of an organism, so as to help maintain internal chemical homeostasis and prevent damage to the body. The dual function of excretory systems is the elimination of the waste products of metabolism and to drain the body of used up and broken down components in a liquid and gaseous state"</em>
Answer:
D. 2.5 x 10 ^-14 Hz
Explanation:
Use wavelength formula: v = f x wavelength
Rearrange formula for frequency.
f = wavelength / v
f = 7.6 x 10 ^-6 / 3.00 x 10 ^8
f = 2.5 x 10^-14 Hz